The major new feature in this release is MODBUS USB support. Previous versions of apcupsd supported MODBUS over serial (RS232). This version adds support for the MODBUS protocol operating over a USB interface. Thanks are due to APC for supporting this development work.

Other less visible changes include a digital signature on the Mac OS X install package for compatibility with systems using Gate Keeper as well as many bug fixes and cleanups to the code base.

Please see the ReleaseNotes for a summary of changes in this release. A ChangeLog is also available with a complete list of commits.

apcupsd-3.14.12 is a maintenance release that addresses a number of small issues in the previous version. It also contains a workaround for an UPS firmware issue that causes killpower to execute repeatedly in a loop, resulting in the UPS continually cycling power. The precise list of affected models is unknown, but the Back-UPS BR models are known to be afflicted and likely many other Back-UPS USB models are as well. If you are utilizing apcupsd with a Back-UPS over a USB interface, it is highly recommended to upgrade to this release.

Please see the ReleaseNotes for a summary of changes in this release. A ChangeLog is also available with a complete list of commits.

Release 3.14.11 adds MODBUS RS232 protocol support for newer APC UPSes. This release also adds digital signatures on the Windows USB driver and the Windows installer package which should make installation on recent versions of Windows easier.

The MODBUS protocol gives access to advanced UPS features on newer UPSes that previously only supported Microlink. A firmware upgrade may be required to enable MODBUS support on some UPSes. Please see the ReleaseNotes for further details.